Donor cell induced CD69 expression and intracellular IL-2 and IL-4 production by peripheral blood lymphocytes isolated from kidney transplant recipients

Flow cytometry assays, which measure CD69 activation and intracellular cyto kine production, have been used to measure peripheral blood lymphocyte (PBL ) responses to in vitro antigen exposure. In the present study, we show tha t, in healthy individuals and immunosuppressed kidney transplant recipients , CD69 expression and intracellular cytokine production by peripheral blood T cells compare favorably to thymidine uptake as a measure of PBL response to alloantigen in mixed leukocyte culture (MLC). Heparinized whole blood f rom 23 healthy individuals was incubated for 24-48 h with 3rd party allogen eic monocytes; blood from twelve kidney transplant recipients was incubated with monocytes from their kidney donor and with monocytes from unrelated i ndividuals. The percentage of T cells expressing surface CD69 or intracellu lar IL-2 or IL-4 was determined by 3-color flow cytometry. We identified 5 donor-specific response patterns in our kidney transplant group. One transp lant recipient was hyporesponsive; his cells did not express CD69 or produc e IL-2 in response to either donor or 3rd party allogeneic cells. All other transplant recipients expressed CD69 and IL-2 in response to 3rd party all ogeneic cells. Two had no response to donor cells (donor-specific hyporespo nsiveness), three had donor-specific anergy (CD69 expression without cytoki ne production in response to donor cells), five had a donor-specific Th1 re sponse (CD69 expression and IL-2 production in response to donor cells), an d one had a donor-specific Th2 response (CD63 expression and IL-4 but not I L-2 production in response to donor cells). Rapid measures of donor-specifi c hyporesponsiveness such as CD63 activation antigen expression and intrace llular cytokine production may prove valuable in monitoring lymphocyte func tion and aid in the long-term management of kidney transplant recipients. ( C) American Society for Histocompatibility and Immunogenetics, 1999 Publish ed by Elsevier Science Inc.